Drones are one of the hottest things in tech right now, but as well as being fun to play with they can be a menace to airports and a hindrance to firefighters. The rules around drone use are still being formed, but here's what you need to know so far.

1. Restrictions on flying

Every drone pilot must adhere to a few basic rules. Most important is the requirement to keep the drone below 400 feet, otherwise it can stray into controlled airspace and collide with a plane or helicopter. Don't fly a drone within 5 miles of any airport unless you have permission from air traffic control. National parks are also off-limits, as are sports stadiums on game days. Your drone must remain within sight at all times, and you must always give way to manned aviation if it comes close. More details are at the "Know Before You Fly" website and the and the FAA's drone website.

2. Making money

Flying a drone might give you all sorts of business ideas, but the FAA has a general restriction against using drones for commercial purposes. Businesses can apply for a "section 333" exemption, which more than a thousand operators have received, but you might need a lawyer to help you go this route. An alternative is to hire one of a growing number of licensed drone operators to perform whatever work you have in mind.

3. Consumer flight

Individuals face far fewer restrictions than businesses. Beyond the basic safety restrictions listed above, there aren't many rules yet for consumers. To get the most out of your drone, consider joining a local flying club, where you can meet other drone owners and deepen your knowledge of flying.

4. Registration

The U.S. has no registration scheme at present but it will very soon. The FAA plans to introduce one this month that requires you to register a name and address in return for a number that you display on your drone. The scheme is intended to be simple, and as such it probably won't be very effective at stopping illegal flights. It will be mandatory, however, so keep an eye on the FAA website for details.

5. Watch out for the big guys

You can fly your drone in most places right now as long as you comply with the basic rules above, but don't count on that always being the case. Google and Amazon are both testing drone delivery systems to let them quickly deliver goods purchased online. That could be convenient for shoppers and lucrative for the companies, but it might not be great for other drone users. Amazon wants half of the airspace available for drone use today to be restricted to high-speed craft like the ones it's developing, while Google wants all drone flights to be computer controlled. Both proposals would give the companies' business plans preference over hobbyists, so keep a close eye on any proposed rules and exercise your right to speak up.